The objective of this project is to determine the effects of microwave radiation on neurological response. Isolated neurons such as the abdominal ganglion of the Aplysia, lobster ganglia, the sciatic nerves of frogs and the saphenous nerves of cats will be exposed to CW, pulsed, and modulated microwave radiation in the specific absorption rate range (SAR) of 0 to 100 mW/g. Fatigue and recovery of the neurons under different modes of stimulation will be studied. The basic mechanisms of interaction will be investigated in cases where changes occur. Experiments to determine if continuous and pulse wave, 2450 MHz microwave radiation increase the fatigue rate or change the vitality of the frog sciatic nerve were completed. Distinct changes in the vitality and refractoriness of the exposed nerve were seen in comparison to the control nerves for SAR's of 10 mW/g and above. No differences in rundown time were observed between the continuous wave and pulse wave exposure using the same average SAR. Exposure of oubain treated nerves eliminated the difference in loss of vitality between the control and exposed nerves. This result indicates that the microwaves interfere with or perhaps inhibit the Na-K pump.